Pencil



Patented Oct. 2, 1934 ETED STATES 1,975,723 yPENCIL Heinrich Jhnssen, Applicatiigi August 24,

Nuremberg, Germany 1933, Serial No. 686,622

Germany September 14, 1932 4 Claims.

This invention relates to pencils with self propelling leads and its object is to provide an improved and simplified construction of such pencils, to enable the pencil to be operated by one hand for the purpose of advancing the lead into writing position or for pressing the lead into the pencil case or body to prevent breakage of the lead when carried in the pocket, and for other purposes which will be more readily understood from the description here following of one convenient embodiment of the invention.

The invention is more particularly directed to improvements in that type of self propelling pencil in which a spring pressed pusher having. rack teeth thereon is provided with suitable detent mechanism, which when operated allow the pusher to adance through a single step and thereby advance the lead `which is mounted to slide in a tared guide or point piece.

According to this invention the rack is pro-s vided: with a plurality, preferably two, sets of rack teeth, the teeth of one set being in staggered relation to the teeth of any other set and the movable detent member is adapted in any position to engage only one set of these rack teeth and in its movement to another position to engage a dierent set, whereby the pusher, under the action of its spring is moved forwards by the amount of the staggering between the sets of rack teeth. The invention also comprises a convenient construction of spring pressed point guide for the lead by means of which the full and eiec-z tive reverse operation of the pusher to cause the lead to recede into the case or guide is assured y even when the lead, through use, is shortened.

The invention further comprises the convenient design and arrangement of the parts which enables the above operations to be effected in a simple and reliable manner.

ln the accompanying drawing which shows one convenient form of the invention:

Figure l is a sectional elevation through a self propelling pencil in accordance with this invention.

Figures 2, 3 and 4 are part sectional views to an enlarged scale and show the detent and racked pusher in diierent positions and illustrate the forward step movement of the pusher.

Figure 5 is a transverse section of the movable detent.

In carrying the invention into effect according to the form shown the body or case 1, which may be made of metal or of any of the well known plastic materials or compositions, is formed with a diameter bore 2 and 3. The Small (Cl. 1Z0-17) diameter 3 is at what is herein referred to as the rear end of the body or case 1 and a pusher 8 of elongated rectangular cross Isection and conveniently of metal strip is a working fit therein. The rear part of this pusher has two sets of rack teeth 6a and 6b on opposite edges of the strip portion. Thel set 6a `as can be seen from Figures 2-4 is staggered in relation to the teeth of the set 6b, the teeth of 6b being set half a pitch in the rear of the teeth of 'the set 6a. As can be seen 4also the front face of the teeth 6c is arranged rat right angles to the axis of the pusher while the rear face 6d is inclined. A movable detent member 9 is formed conveniently of tempered steel and is mounted in a slide 5 which is guided in a transverse bore 4 formed in the body or case 1 a short distance to the rear of the step from the part 2 of larger diameter to the part 3 of smaller diameter bore. Themovable detent plate 9 has an opening 10 formed therein of a width suiiicient to enable vthe pusher 6 to fit laterally therein in Figures 2-4 but this elongated slot 10 is of a length shorter than the width of the pusher. Thus when the slide 5 is pushed down to the position shown in Figure 2, the detent plate 9 rests with the-top end of its slot 10 nested in the bottom of one of the teeth of the set 6a, while the bottom of the slot 10 is just clear of the teeth of the set 6b. In Figure 3 the slide 5 has been moved upwards in the direction of the arrow till the bottom of the slot l0 has entered part way of the depth of the teeth of rack 6b and the top of the slot 10 is just about to clear the top of the teeth of the set 6a. A further movement upwards to the position shown in Figure l allows the pusher 6 to be pressed forward by a spring 8 which engages between the abutment or shoulder 3a and the head 8a on the pusher 6. In the slide 5 there is a slot 5a which embraces the pusher 6 sideways but is of length equal to the height of the pusher 6 in Figures 2-4 plus the travel of the detent 9, with a suitable allowance as can be seen from the drawing.

In order to limit the travel of the pusher. 6 by successive steps a stop piece 11 is threaded into the front part of the enlarged bore 2 and this stop is pierced by a central opening so as to act also as a guide for the stem '1 of the pusher 6. The stem '7 passes further through a central opening in a screwed cap 1'1 which acts as the abutment of a spring 16 which presses on the bushing 15. The bushing 1.5 is guided in the two diameter bore of the point piece 12 which is conveniently tapered externally in the usual manner. The spring 16 it will be seen normally presses the shoulder of the bushing l5 against the shoulder l2@ at the step from the larger to xthe smaller w eter oi the bore of the point piece 12. The length of lead is held and is a good ht in the central bore of the bushing 15 and the end of the stern 7 engages the rear end of the lead i3. Where the bushing 15 projects atfthe front of the point piece 12 it is tapered and split as at 14 in the usual manner whereby the lead i3 is held with a resilient grip.

By pressing the slide 5 one way or the other, which will be determined by which side of the slide is projecting most from the body or case l, 'the rack pusher 6 is released and the pusher advances through one step under the action of the spring e as above described. To cause the lead to recede into the bushing l5 the point of the lead is pressed against the table or some suitable abutment whereby the stem 'l and pusher 6 are moved rearwardly against the action of the spring 3. The inclined face 6d oi' the rack tooth which is nearest to the detent plate 9 operates on the opposite edge of the elongated slot 10 to move the detent 9 and permit the rearward movement of the lead, stem and pusher 6. If the projecting part of the lead is too short to enable the pusher d rto be moved rearwardly through approximately one half pitch of the rack teeth, the pressure on the point causes the bushing 15 to slide rearwardly against the action of the spring 16 whereby the lead is eiectively enclosed and protected while rthe pencil is being carried in the pocket of the user, It is generallypreferable as shown to form the tapered front part 14 of metal while the other parts such as the bushing l5 and the point piece 12 may be made of any suitable casein composition or resinous material of which there are several on the market which lend themselves to ready moulding` l claim:

navegas l. An automatic propelling pencil having a body part, a lead pusher in said body part, detent controlled means cooperating with the lead pusher for moving the lead step by step forwardly, and a spring pressed point member on said pencil movable by a rearward pressure thereon through a space at least the length of one step of said forward member.

2. .an automatic propelling pencil having a body part, detent controlled means in said body part for feeding the lead step by step forwardly, a point guide projecting from said body and closely embracing the lead, said point guide being slidable in said body relatively to said detent means, stop means to limit the forward movement of said point guide, and spring means pushing said point guide against said stop.

3. An automatic propelling pencil having a body part, a lead pusher in said body, a spring pressing said pusher forwardly, datent mechanism for restraining the forward movement of said pusher, but movable to allow said pusher to move forwardly step by step, a point guide for the lead projecting from said body and slidably mounted therein relatively to said pusher, stop means to limit the forward movement of said point guide, and spring means pushing said guide against said stop.-

e. An automatic propelling pencil having a body part, a lead pusher in said body part having two sets of rack teeth formed thereon, a spring pressing said pusher forwardly, a detent slidable transversely to said pusher and adapted to engage alternatively one or the other set of said sets of rack teeth, a point guide for the lead projecting from said body and slidable therein, stop means for limiting the forward movement of said point guide, and a spring pressing said point guide against said stop.

Hammett .lor-nissan.

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